Nine, production-scale, recirculating aquaculture systems were utilized to compare the growth parameters between all-female and mixed sex yellow perch stocks. Each system was stocked with 455 fish m⁻³ and contained one of three different biofilter types: a rotating biological contactor, a trickling filter or a bead filter. The all-female fingerlings (S1) used were originally derived from Lake Mendota, Wisconsin. The mixed-sex fingerlings (S2) used were originally derived from Lake Erie. Temperature and photoperiod (23°C, 16H-L) were maintained at levels for optimal growth. Absolute growth rates ranged from 0.27-0.48 g/day. Mean final density within treatments was 42.8 kg/m³ and ranged from 37.2-50.2 kg/m³. The main effect of stock did not have a significant effect on growth (p > .1). All-female treatments exhibited more uniform growth. The main effect of filter type did have a significant effect on fish growth (p < .01), with fish in tanks containing trickling filters exhibiting significantly higher growth. Total feed conversion averaged 1.61 across all treatments and ranged from 1.38-1.78. S1 treatments consumed a significantly higher percent body weight per day than S2 treatments (p < .05). Analysis of PIT tagged individuals revealed that the mean relative growth rate was significantly higher in S2 individuals (513.9%) compared to S1 individuals (315.3%: p < .01). S2 females (597.8%) grew 1.9 times faster than S1 females (315.3%: p < .01). Within S2 individuals, females (597.8%) grew 1.5 times faster than males (395.2%: p < .05). For all individuals, 33.6% of the variation in final weight was explained by the variation in initial weight. Differences in the geographic strain or culture history of these stocks may have had a larger overall effect on growth than sexual classification (all- female or mixed sex). Dress percentage of skin-on butterfly fillets was examined in 20 individuals per stock and in six groups of 20 individuals per stock. Within S2 individuals, 73.7% were female. Mean fillet yield was significantly greater in S1 individuals (47.6%) compared to S2 individuals (43.0%: p < .01). Mean GSI in S1 individuals (1.01%) was significantly higher than S2 individuals (0.54%: p < .05). Within S2 individuals, mean GSI was significantly higher in females (0.70%) when compared to males (0.08%: p < .05). Fillet yield was significantly greater in S1 groups (47.2%) compared to S2 groups (44.9%: p < .01). Within each stock fillet yield increased with size. The difference in fillet yield demonstrated between these stocks may be a result of differences in strain of origin. The identification of superior yellow perch strains or strain crosses with regard to growth rate and fillet percentage is of considerable importance to the industry. / Master of Science

Cryptococcus laurentii and Cryptococcus flavescens are nonfermenting yeasts forming extracellular polysaccharide capsule. Both species are mainly saprofytic but Cr. laurentii is also known to be an opportunistic pathogen in immunocompromised patients. Cr. flavescens used to be considered a synonym of Cr. laurentii but nowadays it is classified as a separate species that belongs to the phylogenetic group I of the Cr. laurentii group. In the experimental part 28 strains of species Cr. laurentii, Cr. flavescens a Cr. victoriae were biotyped using MALDI-TOF MS. The yeasts were cultivated on three different media (Sabouraud, YPD and potato agar) and three methods were used for the protein extraction. The impact of growth medium composition from which the strains were inoculated on the quality of spectra was studied together with the suitability of individual methods for use on different media. Then the impact of growth medium composition on the quality of acquired spectra was evaluated. Finally, all strains were compared mutually and with the type strain of Cr. laurentii CCY 17 3-2. The composition of the medium cells were inoculated from was found to have little impact on the spectra quality. The same result was determined for the composition of the actual growth medium cells were cultivated on. Crucial for the quality of mass spectrum is the method of cells preparation. Best results were acquired when cultivating cells on YPD agar, washing the cells with ethanol and using mix of sinapinic and ferulic acid as a matrix. Potato agar was found not suitable for cultivating yeasts of the Cryptococcus genus due to significant production of extracellular polysaccharides which complicate the protein isolation process. All strains were compared to Cr. laurentii type strain CCY 17-3-2 and MSP dendrograms were created based on the spectra similarity. In the MSP dendrograms all strains were successfully divided into relevant species on all tested media. Finally sequences of D1/D2 domain of LSU gene were compared and phylogenetic tree was created. This tree was then compared to the MSP dendrograms.

Made available in DSpace on 2014-08-20T14:31:28Z (GMT). No. of bitstreams: 1 dissertacao_eliane_machado_pereira.pdf: 4235511 bytes, checksum: 28dcd80ec8888a8603565a7809054107 (MD5) Previous issue date: 2012-03-15 / This study verified helminth parasites infection in gastrointestinal tract, lungs, heart, and kidneys of southern sea lions, Otaria flavescens, from south coast of Rio Grande do Sul State, Brazil. Twenty-nine sea-lions were found dead on the beaches, whose carcasses had mild state of decomposition, were necropsied. The organs were collected during field necropsies for laboratory analyses were 24 small and large intestines, 24 livers including parenchyma and gall bladder, 29 stomachs, 24 hearts, and 24 pairs of kidneys. The organs were maintained frozen at -20°C until their processing. A sieve with 150µm mesh was used for screening the parasites. All content retained was analyzed under stereomicroscope. The helminthes were collected, counted, fixed in AFA, stained with carmine, and clarified in beechwood creosote. The small intestines were divided into three segments that were separately analyzed to record the distribution of helminthes by preference sites. Kolmorogov-Smirnov test was used to verify the type of data distribution. Comparison of mean abundance of infection between age classes was performed through Wilcoxon test at significant level of 0.05. Correlations between infection intensity, sex, total length of the individual, and length of small and large intestines were determined using Pearson s Correlation. Action® software version 1.1 was applied for statistical analyses. Among 29 specimens of O. flavescens 23 were males, three females, and three individuals whose sex could not be determined. The average length of the animals was 2.14±0.31m (1.58 to 2.64m) including 13 sub-adults and 16 adults. A total of 996 specimens of Contracaecum ogmorhini were recorded, especially in the stomach (10.34% of prevalence), 42,145 specimens of Corynosoma australe (100% of prevalence) and 512 of Bolbosoma turbinella (50% of prevalence) were found. Two species of trematodes were found: Stephanophrora uruguayense (Prev. 4.17%) and Ascocotyle (Phagicola) longa (Prev. 33.33% ), a estimated total of 1,988.202 specimens. Cestodes were found in only one of the hosts (4.16% of prevalence) which presented four scoleces. Macroscopically, liver, gall bladder, heart, lungs, and kidneys did not contain parasites. No significant correlation was observed between infection intensity, mean abundance, sex, total length of the host, or length of intestines. Infections levels were similar between sub-adults and adults sea lions. This is the first record of Diphyllobothrium sp., Bolbosoma turbinella, Contracaecum ogmorhini, Ascocotyle (Phagicola) longa, and Stephanoprora uruguayense in O. flavescens in Brazilian waters. As regards parasite fauna of O. flavescens, our data are different from those previously reported for specimens from Pacific coast of South America. / Este estudo analisou os helmintos parasitos gastrointestinais, pulmonares, cardíacos e renais do O. flavescens no litoral sul do Rio Grande do Sul, Brasil. Foram necropsiados 29 leões-marinhos, cujas carcaças apresentavam baixo estado de decomposição. Os órgãos coletados mediante necropsia a campo para análise em laboratório foram 24 intestinos delgado e grosso, 24 fígados incluindo parênquima e vesícula biliar e 29 estômagos, 24 corações e 24 pares de rins. Os órgãos foram congelados a 20oC até o seu processamento. Para a triagem dos parasitos foi usada peneira com malha de 150 µm e todo o conteúdo retido foi analisado sob microscópio estereoscópico. Os helmintos foram fixados em AFA, corados com Carmin e clarificados com creosoto de Faia. Os intestinos delgados foram divididos em três segmentos que foram analisados separadamente para registrar a distribuição dos helmintos por sítios de preferência. Teste de Kolmorogov-Smirnov foi utilizado para verificar tipo de distribuição dos dados. A comparação da abundância média de infecção entre classes etárias foi realizada através do teste de Teste de Wilcoxon usando nível de significância de 0.05. As correlações entre intensidade de infecção, sexo, comprimento total do individuo e comprimento dos intestinos delgado e grosso foram verificadas usando a Correlação de Pearson. Para as análises estatísticas usou-se o software Action® versão 1.1. De 29 espécimes de O. flavescens 23 eram machos, três fêmeas e em três indivíduos o sexo não pode ser determinado. A média do comprimento total dos animais foi 2,14±0,31m (1,58 - 2,64m), sendo 13 subadultos e 16 adultos. Foram registrados 996 espécimes de Contracaecum ogmorhini presentes principalmente no estômago, (prevalência 10%). Registrou-se 42.145 espécimes de Corynosoma australe (Prev. 100%) e 512 de Bolbosoma turbinella (Prev. 50%). Duas espécies de trematódeos foram coletados: Stephanophrora uruguayense (Prev. 4.17% ) e Ascocotyle (Phagicola) longa (Prev. 33.33% ) totalizando 1.988.202 espécimes. Cestódeos foram encontrados em apenas um hospedeiro (Prev. 4,16%) que apresentou 4 escóleces. Macroscopicamente, fígado, vesícula biliar, coração, pulmões e rins examinados não estavam parasitados. Nenhuma correlação significativa foi observada entre a intensidade de infecção, sexo, comprimento total ou comprimento dos intestinos. Este é primeiro registro de Diphyllobothrium sp., Bolbosoma turbinella e Contracaecum ogmorhini em O. flavescens em águas brasileiras. No que se diz respeito à fauna parasitária de O. flavescens, as espécies encontradas no presente estudo não são as mesmas previamente citadas para leãomarinho-do-sul da costa pacífica da América do Sul.

I investigated the differences in male and female foraging behavior of the african carpenter bee Xylocopa flavescens (Hymenoptera: Apidae). This species is important big pollinator in study area as observed. The pollen loads from the 20 male and 20 female bees were compared for the analysis of the foraging pattern. The principal differences and trends were found for the range of flowers visited by each sex.

I investigated the differences in male and female foraging behavior of the african carpenter bee Xylocopa flavescens (Hymenoptera: Apidae). This species is important big pollinator in study area as observed. The pollen loads from the 20 male and 20 female bees were compared for the analysis of the foraging pattern. The principal differences and trends were found for the range of flowers visited by each sex.

Orientadores: Francisco Maugeri Filho, Gonçalo Amarante Guimarães Pereira / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos / Made available in DSpace on 2018-08-25T00:15:25Z (GMT). No. of bitstreams: 1 Andrade_CristianeContePaimde_D.pdf: 8118229 bytes, checksum: e37327c8c0a8a32ecfc89552e46cbd0d (MD5) Previous issue date: 2014 / Resumo: Xilanases são enzimas que hidrolisam as ligações glicosídicas entre as unidades de xilose que compõem a xilana, o principal constituinte hemicelulósico. Devido à grande disponibilidade desse tipo de material na natureza, as xilanases podem ser empregadas em diversos ramos, como nas indústrias têxtil, de alimentos e de rações, na bioconversão de resíduos lignocelulósicos, no clareamento de papel e polpa, e no tratamento de resíduos. Visando descrever novas enzimas para futuras aplicações, este trabalho teve como objetivo purificar e caracterizar a xilanase produzida pelo basidiomiceto Cryptococcus sp. LEB-AY10, uma levedura previamente isolada da Mata Atlântica e selecionada pela produção de enzima termoestável. Para tanto, o micro-organismo foi inicialmente identificado em nível de espécie e depositado como C. flavescens LEB-AY10 (CCT 7725); em sequência, foi estudada a produção da enzima utilizando, como substrato, bagaço de cana-de-açúcar, pré-tratado por explosão a vapor em três diferentes condições, bem como suas respectivas frações solúveis, e suplementados com melaço ou componentes sintéticos. Tendo sido definida a metodologia de tratamento do bagaço, técnicas de planejamento experimental foram utilizadas para estudar a influência das variáveis de cultivo e aumentar a atividade da xilanase produzida. Nas condições otimizadas, obteve-se aumento de 5,6 vezes na atividade em relação aos testes iniciais, atingindo 4,67 U/mL (a 50°C) ou 8,33 U/mL (a 80°C) em 96 h de incubação. Posteriormente, realizou-se a purificação da xilanase em duas etapas cromatográficas (troca iônica e permeação em gel), sendo possível recuperar 45% da atividade inicial. A massa molecular média foi estimada em 48 kDa. A enzima apresentou atividade ótima a 77,5°C e maior estabilidade em pH próximo a 5,3. Neste pH, as meias-vidas desta enzima foram estimadas em 9,2 minutos a 77,5°C e 33,74 h a 67°C. Os parâmetros cinéticos Km e vmax utilizando xilana de bétula (birchwood) como substrato foram 4,13 g/L e 2,32 U/mL, respectivamente. A xilanase purificada apresentou baixas atividades de ?-xilosidase em 4-nitrofenil-?-D-xilopiranosídeo (0,02 U/mg) e de celulase em carboximetilcelulose (0,99 U/mg). Os produtos de hidrólise da xilana de faia (beechwood) pela xilanase de C. flavescens LEB-AY10 foram, principalmente, xilobiose e xilotriose. Para identificação do gene responsável pela produção da xilanase, foram utilizadas três estratégias: amplificação com primers degenerados, identificação de peptídeos por espectrometria de massas e sequenciamento do genoma da levedura. Um único gene (1265 pb) denominado Xyn10Cf foi identificado e o correspondente cDNA (1035 pb) foi clonado em Escherichia coli DH10B. O gene é interrompido por 6 íntrons, codifica um peptídeo sinal composto por 13 aminoácidos e a proteína madura é formada por 331 aminoácidos, tendo sua massa molecular estimada em 37,1 kDa (podendo conter cerca de 11 kDa de glicosilação). Com base na sequência de nucleotídeos e na caracterização da enzima purificada, a proteína foi classificada como membro da família GH10. Por fim, para comprovar a funcionalidade do gene identificado Xyn10Cf foi realizada a expressão na linhagem de Pichia pastoris GS115 sob o controle dos promotores álcool oxidase 1 (AOX1) ou gliceraldeído-3-fosfato desidrogenase (GAPDH), atingindo 5,66 U/mL e 7,67 U/mL, respectivamente, para 84 h de indução em frascos agitados / Abstract: Xylanases are enzymes that hydrolyze the glycosidic bonds between the xylose units of xylan, the main hemicellulosic compound. Due to the high availability in nature of this kind of material, the xylanases may be used in a wide range of industrial plants, including: textile, food and feed industries, bioconversion of lignocellulosic wastes, biobleaching of paper and pulp, and waste treatment. In order to describe novel enzymes for future applications, the goal of this work is to purify and characterize the xylanase produced by the basidiomycete Cryptococcus sp. LEB-AY10, a yeast previously isolated in the Atlantic Forest and selected by the production of a thermostable enzyme. First, the microorganism was identified at the species level and deposited as C. flavescens LEB-AY10 (CCT 7725); then, enzyme production was studied using the substrate sugarcane bagasse, pretreated by steam explosion in three different conditions, as well their corresponding soluble fractions, and supplemented with molasses or synthetic compounds. After selection of the treatment, experimental design techniques were used to assess the influence of cultivation variables and to increase the activity of produced xylanase. At optimized conditions, it was possible to increase activity by 5.6 times from initial assays, reaching 4.67 U/mL (at 50°C) or 8.33 U/mL (at 80°C) after 96 h of incubation. Later, the purification of the xylanase was performed in two chromatographic steps (ion exchange and gel permeation), in which it was possible to recover 45% of initial activity. The average molecular weight was estimated at 48 kDa. The enzyme showed optimal activity at 77.5°C and it was most stable at pH values near 5.3. At this pH, the half-lives of this enzyme were 9.2 min at 77.5°C and 33.74 h at 67°C. The kinetic parameters Km and vmax for Birchwood xylan were 4.13 g/L and 2.32 U/mL, respectively. The purified xylanase showed low activity of ?-xylosidase on 4-nitrophenyl-?-D-xilopiranosídeo (0.02 U/mg) and also showed some cellulase activity on carboxymethylcellulose (0.99 U/mg). The hydrolysis products of Beechwood xylan by the xylanase from C. flavescens LEB-AY10 were mainly xylobiose and xylotriose. For identification of the gene responsible for xylanase production, three strategies were used: amplification of degenerated primers, identification of peptides by mass spectrometry and yeast genome sequencing. A single gene (1265 pb) named Xyn10Cf was identified and the corresponding cDNA (1035 pb) was cloned into Escherichia coli DH10B. The gene is interrupted by 6 introns, it codifies a signal peptide of 13 amino acids and the mature protein is composed by 331 amino acids, with an estimated molecular mass of 37.1 kDa (it may contain around 11 kDa of glycosilation). Based on nucleotide sequencing and on characterization of the purified enzyme, the protein was classified as a member of GH10 family. Finally, to prove the functionality of the identified gene Xyn10Cf, the expression in Pichia pastoris GS115 strain was performed under the control of alcohol oxidase 1 (AOX1) and glyceraldehyde-3-phosphate dehydrogenase (GAPDH) promoters, reaching 5.66 U/mL and 7.67 U/mL, respectively, after 84 h of incubation in shaker flasks / Doutorado / Engenharia de Alimentos / Doutora em Engenharia de Alimentos

Fatty acids (FAs) are used as trophic markers in aquatic food web studies, but few studies have quantified individual variability in FAs profiles over several sites in a range of conditions. I investigated whether FAs profiles of yellow perch (YP), Perca flavescens, vary with body size and between lakes with and without largemouth (Micropterus salmoides), and smallmouth bass (Micropterus dolomieu), the most common and abundant piscivores in lakes of the region. I analyzed the FAs of YP as well as zooplankton, benthic invertebrates, and prey fish collected from eight lakes where bass were either present or absent in the Outaouais region over the summer of 2016. I compared the growth rate of YP between the lakes and the YP in lakes without bass exhibited a slower growth rate. I also compared the FA signatures of YP using redundancy analysis (RDA). 23 FAs could be identified and quantified. FAs profiles were dominated by palmitic- (16:0), oleic- (18:1), stearic- (18:0), and palmitoleic acid (16:1). The RDA analysis based on FAs profiles of YP revealed variation along two main gradients (the presence of bass and the date of capture). The first two eigenvectors accounted for 42.1% of the variation (RDA1=27.6% and 2=14.6%). Arachidonic (20:4) and docosatrienoic (22:3) were the most correlated FAs with RDA1. Due to the sampling period, it was impossible to determine if the observed effects were due to the date of capture, the presence of bass, or a change in metabolism, but the last two were deemed as the most plausible explanations. It was concluded that the utility of FA signatures to quantify diet in natural environments is limited and that FAs might be more successful as markers in primary consumers and other lower trophic levels. It is recommended that a combination of FAs, stable isotopes, and modelling should be used in the future.

No description available.

No description available.

La perchaude (Perca flavescens) constitue une ressource socioéconomique de grande importance dans le Lac Saint-Pierre (Québec, Canada). Bien que ce lac fluvial soit désigné réserve de la biosphère par l’UNESCO, le statut de la perchaude est préoccupant. Afin de permettre à l’espèce de persister en fonction des diverses pressions anthropiques, il est important de comprendre sa dynamique populationnelle et les mécanismes qui en sont responsables. La perchaude est connue pour sa philopatrie ; le fait de toujours se reproduire à son site de naissance peut entraîner la subdivision d’une espèce en de multiples populations, où chacune pourra être pourvue d’adaptations locales distinctes. Il est possible d’étudier ces processus à l’aide des signaux génétiques associés à la reproduction des individus. Toutefois, une faible différentiation génétique entre les populations du Lac Saint-Pierre est envisagée en raison de la colonisation récente du système (moins de 8000 ans). L’objectif de cette étude est de déterminer s’il existe plusieurs populations de perchaude dans le Lac Saint-Pierre. Les simulations réalisées ont révélé que l’utilisation de marqueurs AFLP (amplified fragment length polymorphism), permettant une analyse globale du génome, affiche une meilleure détection de la différentiation des populations que celle des marqueurs microsatellites. Afin d’associer les individus à leur site de naissance, la méthode d’AFLP et des microsatellites ont été utilisées sur des larves capturées suite à l’éclosion des oeufs. Trois analyses distinctes d’AFLP ont indiqué une corrélation entre la composition génétique des individus et des sites géographiques, confirmant ainsi la présence de plusieurs populations sympatriques dans le Lac Saint-Pierre, découlant vraisemblablement de la philopatrie de l’espèce. L’absence de différentiation génétique relatée par les marqueurs microsatellites vient confirmer l’importance du choix des marqueurs génétiques. Bien que la différentiation génétique observée soit relativement faible, la gestion de la perchaude devrait tenir compte de la dynamique des populations distinctes dans ce système. / Yellow perch (Perca flavescens) is a commercially-exploited freshwater fish species in Lake Saint-Pierre (Quebec, Canada). Even if this fluvial lake is designated as a biosphere reserve by UNESCO, the yellow perch status is of concern. To ensure the persistence of species facing to anthropogenic pressures, understanding dynamics and mechanism that structure populations are of major importance. Because the habitat characteristics are spatially structured and this species is known to display natal site fidelity, a subdivision of the species in multiple populations and local adaptations may occur. It is possible to detect these processes according to genetic signal associated with individuals’ reproduction. However, low genetic differentiation is hypothesised due to the recent colonization of the system (< 8 K years). This study aims at determining if there are multiple populations of yellow perch in Lake Saint-Pierre. Simulations was first performed to confirm that population differentiation is better depicted by amplified fragment length polymorphism (AFLP) than microsatellite markers. In order to associate individuals to their site of birth, larvae captured after hatching were used. A survey of the variation throughout the entire genome was then performed by using the AFLP approach and variations at microsatellite loci were used to further investigate the organization of these populations. Three distinct AFLP analyses indicated a correlation between genetic composition of individuals and spawning sites, and thus confirmed the presence of multiple sympatric populations in Lake Saint-Pierre, resulting likely from natal site fidelity. At the opposite, the lack of genetic differentiation reported by microsatellites markers confirms the importance of the choice of genetic markers. While the genetic differentiation is very low, the management of this species should take into account the existence of distinct population structures in this system.